The property loader example ships with TestStand.
It can be found at /Examples/LoadingLimits/LimitsFromTextFile/
For more information about the Property Loader Step Type, refer to Appendix D in the TestStand Reference manual.
Keep in mind, this CANNOT read a generic text file and give you a string. In that case you will need to write a code module (in LabVIEW, CVI, C++, etc...) and have it return you the string as a parameter. Is this the example you are referring to?
Allen P.
NI